max10 adc sample point

Question

hi everyone:

i try to use max10 on chip adc to sample a image sensor output. the frequence is 1MHz.

i need to know when the max10 on chip adc switch from sample to the hold mode. in most adc, this is controlled by the CONVST signal.

acctually i can test the sample point by

1.applying a 1MHz sin signal to the adc input,

2.set the adc sample frequence to 1MHz, the adc will generate a valid signal every 1μs

3.put the sin signal and the adc valid signal on the oscilloscope

4.figure out the relationship between valid signal and the sample point.

the problem is :

1. i can not get the precise result

2. i can not make sure every max10 has the same result

but i still want to find the relationship between valid signal and the sample point on manual.

altera_forum · Answer

i use my method to test the sampe point on MAX10_10M08_Evaluation_Kit,

the result shows in sample_point.jpg

be careful, it is 5*clock_clk not 5* adc_pll_clock_clk!

the test condition is:

1. only use adc channel 1

2. 1MHz speed

as follows:

altera_forum · Answer

almost 15 months passed,  i still do not find the answer. i check the latest adc user guide(20171215), no describtion about the adc sampling point.

altera_forum · Answer

i some one find the answer, please share me. thanks!

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